1. Field of the Invention
This invention relates to a novel additive composition for use in motor fuels. The additive comprises the reaction product obtained by reacting a 4-alkyl-2-morpholinone with an alkoxypolyoxyalkylene amine to produce a motor fuel--soluble amido alkanolamine compound which provides a number of valuable properties in a motor fuel composition.
The combustion of a hydrocarbon motor fuel in an internal combustion engine leads to the formation and accumulation of deposits on various parts of the combustion chamber as well as on the fuel intake and exhaust system of the engine. The presence of deposits in the combustion chamber seriously reduces the operating efficiency of the engine. First, deposit accumulation within the combustion chamber inhibits heat transfer between the chamber and the engine cooling system. This leads to higher temperatures within the combustion chamber, resulting in increases in the end gas temperature of the incoming charge. Consequently, end gas auto-ignition occurs causing engine knock. In addition, the accumulation of deposits within the combustion chamber reduces the volume of the combustion zone, causing a higher than design compression ratio in the engine. This, in turn, can also lead to engine knocking. A knocking engine does not effectively utilize the energy of combustion. Moreover, a prolonged period of engine knocking can cause stress fatigue and wear in pistons, connecting rods, bearings and cam rods of the engine. The phenomenon noted is characteristic of gasoline powered internal combustion engines. It may be overcome by employing a higher octane gasoline which resists knocking for powering the engine. This need for a higher octane gasoline as mileage accumulates has become known as the engine octane requirement increase (ORI) phenomenon. It is particularly advantageous if engine ORI can be substantially reduced or eliminated by preventing or modifying deposit formation in the combustion chambers of the engine.
Another problem common to internal combustion engines is the formation of intake valve deposits. Intake valve deposits interfere with valve closing and eventually will lead to valve burning. Such deposits interfere with valve motion and valve seating and tend to reduce the volumetric efficiency of the engine and to limit the maximum design power. Valve deposits may be produced from thermally and oxidatively unstable fuel or from lubricating oil oxidation products. The hard carbonaceous deposits produced collect in the tubes and runners that are part of the exhaust gas recirculation (EGR) flow. These deposits are believed to be formed from exhaust particles which are subjected to rapid cooling while mixing with the air-fuel mixture. Reduced EGR flow can result in engine knock and in nitric oxide, NO.sub.x, emission increases. It would therefore be desirable to provide a motor fuel composition which minimizes or overcomes the formation of intake valve deposits.
2. Disclosure Statement
U.S. Pat. No. 4,747,851 discloses a noval polyoxyalkylene diamine compound of the formula: ##STR3## where c has a value from about 5-150, b+d has a value from about 5-150, and a+e has a value from about 2-12. Motor fuel compositions comprising the novel polyoxyalkylene diamine, alone or in combination with a polymer/copolymer additive are also disclosed.
U.S. Pat. No. 4,659,337 discloses the use of the reaction product of maleic anhydride, a polyether polyamide containing oxyethylene and oxypropylene ether moieties, and a hydrocarbyl polyamine in a gasoline motor fuel to reduce engine ORI and provide carburetor detergency.
U.S. Pat. No. 4,659,336 discloses the use of the mixture of (i) the reaction product of maleic anhydride, a polyether polyamine containing oxyethylene and oxypropylene ether moieties and a hydrocarbyl polyamine, and (ii) a polyolefin polymer/copolymer as an additive in motor fuel compositions to reduce engine ORI.
U.S. Pat. 4,631,069 discloses an alcohol-containing motor fuel composition which additionally comprises an anti-wear additive which is the reaction product of a dibasic acid anhydride, a polyoxyisopropylene diamine of the formula: ##STR4## where x has a value of 2-68, and an N-alkyl-alkylene diamine.
U.S. Pat. No. 4,643,738 discloses a motor fuel composition comprising a deposit-control additive which is the reaction product of a dibasic acid anhydride, a polyoxyisopropylene diamine of the formula: ##STR5## where x has a value of 2-50, and an N-alkyl-alkylene diamine.
U.S. Pat. No. 4,604,103 discloses a motor fuel deposit control additive for use in internal combustion engines which maintains cleanliness of the engine intake system without contributing to combustion chamber deposits or engine ORI. The additive disclosed is a hydrocarbyl polyoxyalkylene polyethylene amine of molecular weight range 300-2,500 having the formula: ##STR6## where R is a hydrocarbyl radical of from 1 to about 30 carbon atoms; R' is selected from methyl and ethyl; x is an integer from 5 to 30, and R'' and R''' are independently selected from hydrogen and --(CH.sub.2 CH.sub.2 NH)y--H, where y is an integer from 0 to 5.
U.S. Pat. No. 4,581,040 discloses the use of a reaction product as a deposit-inhibitor additive in fuel compositions. The reaction product is the condensation product of the process comprising (i) reacting a dibasic acid anhydride with a polyoxyisopropylene diamine of the formula: ##STR7## where x is a numeral of about 2-50, thereby forming a bismaleamic acid; (ii) reacting said maleamic acid with a polyalkylene polyamine, thereby forming a condensate product; and (iii) recovering said condensate product.
Co-pending application Ser. No. 07/896,700 discloses alkylphenoxypolyoxyalkylene amidoalkanolamines.
U.S. Pat. No. 4,357,148 discloses a motor fuel additive useful in controlling ORI which is the combination of (a) an oil-soluble aliphatic polyamine containing at least one olefinic polymer chain, and (b) a polymer, copolymer, or corresponding hydrogenated polymer or copolymer of a C.sub.2 -C.sub.6 mono-olefin with a molecular weight of 500-1,500.
U.S. Pat. No. 4,234,321 discloses a hydrocarbylpoly(oxyalkylene) ureylene carbamate as a deposit control additive for fuels.
EP 297996 discloses an alkylphenylpoly(oxypropylene) aminocarbamate having a molecular weight ranging from 600 to 6000 for use in gasoline or diesel fuel compositions.
An object of this invention is to provide a novel additive reaction product which may be employed in fuel compositions and particularly in a motor fuel composition.
Another object is to provide a fuel additive reaction product and a motor fuel composition which inhibits the formation of intake valve deposits in an internal combustion engine.
Another object of this invention is to provide a fuel additive and a fuel composition which inhibits or reduces the formation of combustion chamber deposits in an internal combustion engine.
Yet another object of this invention is to provide a concentrate composition which may be added to a motor fuel to provide motor fuel compositions of the instant invention.